Annie Leibovitz has learned to hunt for bargains since she refinanced a $24 million loan last year. The photographer just bought four Eames aluminum chairs for her office from Design Within Reach on Columbus Avenue. The price is about $8,000, according to lifestyle author Bruce Littlefield, but an insider said Leibovitz got a big discount because the chairs were on sale. But apparently the saving wasn’t enough — the shutterbug’s rep said she’s had second thoughts and is returning the merchandise.